1. Field of the Invention
The present invention relates to cartridge loading cameras, and more particularly to apparatus for regulating exposure in response to sensing a cartridge film sensitivity code.
2. Description of the Prior Art
Frequently, it is desirable to provide cartridge loading cameras with the capability to expose film having various film speeds. In doing so, it is especially useful to use film speed identification encoded on the film cartridge. The indicator, or code, may be sensed and the exposure regulated to compensate for the variation in film speed. Such code sensing and exposure adjustment eliminates the need for the camera user to separately alter the camera to compensate for different film speeds. It is known to adjust an exposure aperture in response to movement of a locking member of a camera cartridge receptacle door and to use the force provided from the inserted cartridge to adjust the exposure regulating apparatus such as a filter to provide proper exposure. Conventionally, the cameras are constructed so that the cartridge is inserted against a biasing mechanism that may adjust a filter. This bias tends to unseat the cartridge, thereby disturbing the position of the film plane within the camera. This condition may also be aggravated by the fact that movement of the apparatus to adjust the aperture or move the filter may be a greater distance than the available stroke of the cartridge insertion. The unseating force that is exerted on the cartridge is therefore increased by an amount related to the leverage necessary to attain the desired travel of the exposure regulating apparatus.